Full Sequence Bleaching with Dimethyldioxirane

Research work to date has shown dimethyldioxirane to be a very powerful, yet highly selective oxidant. Dimethyldioxirane bleaching may become more important in the future with legislative restrictions on chlorine based bleaching agents as it contains no chlorine. Most work with dimethyldioxirane to date has concentrated on short sequence bleaching, or the use of peroxymonosulfate as a pre-treatment to improve oxygen delignification. The goal of this study was to develop a full sequence bleaching containing only dimethyldioxirane and other chlorine free bleaching agents that matched the brightness and strength characteristics of comparable chlorine dioxide based full sequences. Dimethyldioxirane was found to match the strength, but not the brightness of, chlorine dioxide. As well, dimethyldioxirane may be harsher on cellulose than chlorine dioxide. Additional optimization may allow dimethyldioxirane to perform as well as chlorine dioxide. It was seen that increased brightnesses were achieved by using optimum conditions and a step-wise chemical addition. As well, the addition of peroxide to dimethyldioxirane stages may increase brightness

Contributions to the performance of thin film capacitors for high reliability applications

Capacitors are critical devices in microelectronic assemblies that must be incorporated into electronic systems through a variety of ways such as integrated or discrete devices. This work has developed new thin film capacitors deposited directly onto multichip module or printed circuit board surfaces to benefit from closer integration that enhances system performance for use in high reliability applications. The capacitors serve as filters or provide tuning and energy storage functions. Unexpected performance was observed during development that included low adhesion of the films to the substrates, higher effective dielectric constants than reported in literature, and low yields. Three publications resulted from this work with Paper I presenting a study of thin films on low temperature cofired ceramic (LTCC) and their reliability for multiple functions. The thin film and LTCC system are modeled with results suggesting a mechanism of enhancing thin film adhesion to the LTCC through a combination film composition and surface modification. Paper II presents measurements of dielectric properties of thin film capacitors on LTCC. Multiple mechanisms are detailed that contribute to the measured dielectric constant values of the capacitors. One case is modeled to determine the extent of dielectric constant enhancement from fringe fields related to capacitor dimensions. Paper III describes the behavior of thin film capacitors with varying electrode compositions and configurations. Trends are observed that suggest energy band overlap and electrode work functions are influential in dielectric properties and yield of the capacitors. A preferred electrode composition and configuration is suggested based on the capacitor performance --Abstract, page iii

An Effective Electric Dipole Model for Voltage-Induced Gating Mechanism of Lysenin

Lysenin is a pore-forming toxin, which self-inserts open channels into sphingomyelin containing membranes and is known to be voltage regulated. The mechanistic details of its voltage gating mechanism, however, remains elusive despite much recent efforts. Here, we have employed a novel combination of experimental and computational techniques to examine a model for voltage gating, that is based on the existence of an “effective electric dipole” inspired by recent reported structures of lysenin. We support this mechanism by the observations that (i) the charge-reversal and neutralization substitutions in lysenin result in changing its electrical gating properties by modifying the strength of the dipole, and (ii) an increase in the viscosity of the solvent increases the drag force and slows down the gating. In addition, our molecular dynamics (MD) simulations of membrane-embedded lysenin provide a mechanistic picture for lysenin conformational changes, which reveals, for the first time, the existence of a lipid-dependent bulge region in the pore-forming module of lysenin, which may explain the gating mechanism of lysenin at a molecular level

Motor unit identification in two neighboring recording positions of the human trapezius muscle during prolonged computer work

Work-related shoulder-neck pain is a major health risk in computer operators. To understand the physiological mechanisms behind the development of these disorders, EMG recordings of some minutes up to several hours must be accurately decomposed. For this reason we developed EMG-LODEC, an automatic decomposition software program, especially designed for multi-channel long-term recordings of signals detected during slight muscle movements. The subjects executed a 30-min computer task to simulate real work conditions while working at an ergonomically designed workstation. Six-channel intramuscular EMG signals were recorded from two positions of the upper trapezius muscle. The EMG signals were decomposed into individual motor unit action potential trains using EMG-LODEC. The study design enabled us first to study the dependence of intramuscular analysis on the insertion points and second to test the accuracy of the decomposition technique under laboratory conditions during a real experiment. The two positions yielded 887 motor units - 452 located in position 1 and 435 in position 2. Although the numbers of detected action potentials were strongly correlated between the two insertion positions, different motor units were mostly recorded. In particular, the detection of continuously active motor units is specific for the selected insertion points and may not be representative of a muscle, not even for parts with common functions. The approach for the quantitative evaluation of the decomposition technique was to independently decompose two signals that were simultaneously detected by separate sets of wire electrodes placed close to each other in the muscle. Common trains discovered in each signal were compared for consistency. A cross-correlation analysis was performed to find corresponding motor unit pairs that were concurrently active. Concurrently active motor units were found in six subjects. For these motor units the extent of simultaneous occurrence of motor unit action potentials between the two positions ranged from 23% to 78% depending on the distinction of the single motor units and the number of superimposed motor unit action potentials. High concordance was seen in 3 out of the 15 motor unit pairs. Based on the results, EMG-LODEC is capable of providing reliable decompositions with satisfying accuracy and reasonable processing time. EMG-LODEC is suitable for the study of motor unit discharge patterns and recruitment order in subjects with and without musculoskeletal pain during long-term measurements to study work-related musculoskeletal disorder

National Time Accounting: The Currency of Life

This monograph proposes a new approach for measuring features of society’s subjective well-being, based on time allocation and affective experience. We call this approach National Time Accounting (NTA). National Time Accounting is a set of methods for measuring, comparing and analyzing how people spend and experience their time -- across countries, over historical time, or between groups of people within a country at a given time. The approach is based on evaluated time use, or the flow of emotional experience during daily activities. After reviewing evidence on the validity of subjective well-being measures, we present and evaluate diary-based survey techniques designed to measure individuals’ emotional experiences and time use. We illustrate NTA with: (1) a new cross-sectional survey on time use and emotional experience for a representative sample of 4,000 Americans; (2) historical data on the amount of time devoted to various activities in the United States since 1965; and (3) a comparison of time use and wellbeing in the United States and France. In our applications, we focus mainly on the Uindex, a measure of the percentage of time that people spend in an unpleasant state, defined as an instance in which the most intense emotion is a negative one. The U-index helps to overcome some of the limitations of interpersonal comparisons of subjective well-being. National Time Accounting strikes us as a fertile area for future research because of advances in subjective measurement and because time use data are now regularly collected in many countries.

Probabilities of cooperative moves in all 67 symmetric ordinal two-player two-moves games

The symmetric 2x2 one-shot game is one of the simplest and most commonly used representations of strategic conflict. Among others, it includes the prisoner’s dilemma, the game of chicken, the volunteer’s dilemma, and the assurance game. All of these games share three characteristics: (1) both players have to make a single choice between two options; (2) they decide simultaneously; and (3) the payoff structure is symmetric. Typically, social scientists who examine (symmetric) 2x2 one-shot games either focus on one game or compare a small number of such games. There are comparatively few studies which analyzed (symmetric) 2x2 one-shot games in a more comprehensive manner. The goal of the present paper is to initiate research on the strategies people use to play any or all symmetric ordinal two-player two-moves games. We propose comparisons between eight different strategies. As will be shown, this analysis lays the groundwork for many possible follow-up projects

The Role of Certainty in a Two-Person Volunteer’s Dilemma

In the standard volunteer’s dilemma (VoD), a single prosocial act (i.e., volunteering) yields the optimal overall outcome. Whereas the volunteer’s outcome is certain, the defector’s outcome depends on what others do. This research addressed the confounding of prosocial responses with uncertainty avoidance in the standard VoD. In Experiment 1, participants (N = 102) considered 18 hypothetical one-shot two-person VoD scenarios with certain, risky, and uncertain outcomes when volunteering. In Experiment 2, participants (N = 496) considered three hypothetical one-shot two-person VoD scenarios; a certain VoD and two uncertain VoDs of which one had a lower expected collective outcome of volunteering than the certain VoD and the other a higher one. Results suggest that volunteering does not reflect a desire to avoid uncertainty but to maximize expected collective outcomes, reinforcing the assumption that the high volunteering rates we see in a standard VoD are due to social/moral preferences and social projection

The role of certainty in a two-person volunteer’s dilemma

In the standard volunteer’s dilemma (VoD), a single prosocial act (i.e., volunteering) yields the optimal overall outcome. Whereas the volunteer’s outcome is certain, the defector’s outcome depends on what others do. This research addressed the confounding of prosocial responses with uncertainty avoidance in the standard VoD. In Experiment 1, participants (N = 102) considered 18 hypothetical one-shot two-person VoD scenarios with certain, risky, and uncertain outcomes when volunteering. In Experiment 2, participants (N = 496) considered three hypothetical one-shot two-person VoD scenarios; a certain VoD and two uncertain VoDs of which one had a lower expected collective outcome of volunteering than the certain VoD and the other a higher one. Results suggest that volunteering does not reflect a desire to avoid uncertainty but to maximize expected collective outcomes, reinforcing the assumption that the high volunteering rates we see in a standard VoD are due to social/moral preferences and social projection